I went over there and that's a ton to read from a laymen's perspective but I fail to see where anyone, kbertsche, Baumbgardner, or anyone over there is getting "their ass handed to them."

Unfortunately, and no disrespect intended, I think that is because of your lack of experience in reading scientific debate. Baumgardner lost just about all credibility in his first reply, sounding like an undergrad on a usenet sci group. This is followed by his extensive back peddling, selective replies, obsfuscation, and continued ass-hattery. Yes, there is some actual back-and-forth content hidden within the noise, but it is limited. If Baumgardner had conveyed himself in the manner of Bertsche and Morton, he may not have suffered the resulting complete loss of scientific credibility. As it stands, I wouldn't hire him as the liquid nitrogen loader...

The (sad?) fact is that just about every creationist I meet on the internet makes me think - idiot - from presentation if not content. This applies to our own EvC Kaichos Man, Ichiban, etc, all the way up to Baumgardner and Humphreys (Humphreys is in my field and his bullshit makes Baumgardner look a complete amateur) That is why I hope (and expect) that neither you nor Slevesque will remain creationists for much longer, as you are ruining my extrapolation of the above observation into a general rule...

I went over there and that's a ton to read from a laymen's perspective but I fail to see where anyone, kbertsche, Baumbgardner, or anyone over there is getting "their ass handed to them."

The most humorous portion of that discussion was where Baumgardner tried to claim that lake varves, with insect and leaf debris sorted by minute differences in carbon 14, were created by earthquakes. If you can't sense how pathetic this argument is then you should not be allowed to use the verb "see" in this forum any longer.

Figure 1 shows the varve and 14C chronologies as a function of depth of the SG core. Until now, the varve numbers have been counted in the 10.42-30.45 m deep section. The Lake Suigetsu floating varve chronology consists of 29,100 varves. As shown in Figure 1 the sedimentation or annual varve thickness is relatively uniform (typically 1.2 mm yr-1 during the Holocene and 0.62 mm yr-1 during the Glacial). The age below 30.45 m depth is obtained by assuming a constant sedimentation in the Glacial (0.62 mm yr-1). The 14C ages at 10.42, 30.45 and 35 m depth are ca. 7800, 35,000 and 42,000 BP, respectively.

Note the correlation between C-14 and depth with C-14 and varve count. See how at about 11,000 years ago ("BP" means "before present" with "present" defined as 1950 CE), both show a matching change in slope of the curves with depth.

When you realize that one is a linear system of varve counting and the other is a mathematical model based on actual measurements that are along an exponential distribution:

Graph of actual 14C content versus actual time intervals from time "X"

There is no rational reason for the 14C curve to make the same change in slope at the same time as the varve age curve, unless it measures the same thing that the varve counting does - age.

This is another example of internally consistent correlations of three sets of information from the same basic data source: age, depth and 14C/12C radiometric age.

I've not seen a single creationist explanation of this relationship.

Anyone want to correlate 11,000 years ago with major climate change that would alter the rate of deposition of sediment?

The conclusion of ASA Executive Director, Randy Isaac is strongly worded, but accurate:

Randy Isaac writes:

The ASA does not take a position on issues when there is honest disagreement among Christians provided there is adherence to our statement of faith and to integrity in science. Accordingly, the ASA neither endorses nor opposes young-earth creationism which recognizes the possibility of a recent creation with appearance of age or which acknowledges the unresolved discrepancy between scientific data and a young-earth position. However, claims that scientific data affirm a young earth do not meet the criterion of integrity in science. Any portrayal of the RATE project as confirming scientific support for a young earth, contradicts the RATE project’s own admission of unresolved problems. The ASA can and does oppose such deception.

quote:Also, it would seem to me that even with a bouncy background you could at least use known concentrations of 14C to create a linear regression and extrapolate the background and measure the std. error. Anything within the std. error compared to background could be considered zero. Perhaps the problem here is that radiocarbon age is not represented by the amount of carbon 14 but by the calculated age which does not relate the data to the actual background in the experiment.

It's done pretty much the way you are thinking. Radiocarbon measurements are generally done by measuring radiocarbon ratios or concentrations (or a proxy for them), and this is where the backgrounds and normalizations are done. We would typically have at least one background radiocarbon-dead sample and at least one modern calibration standard for a set of unknowns. We would tune up the machine on a calibration standard and come back to it periodically during the run, and would also measure the dead samples a few times during the run. Then, as you imply, we could see how the backgrounds and calibrations varied throughout the run and could do linear fits between these known points. Only after all corrections are done is the result turned into a date BP, then this is converted to a calibrated BC/AD date.

The end result is an estimate or guess of what the age of the article is, and it should be given no more weight than that.

Sorry, this is wrong. Radiocarbon dating provides a pretty accurate assessment of the age of an article when it is done correctly. And scientists have an incentive to do their dating correctly, as there is no respect in science for mistakes and even less for fraud.

But your problem seems to be that you don't like the results of radiocarbon dating.

You don't know the science behind radiocarbon or other forms of radiometric dating, but you come on here and tell scientists who do know -- and who have studied the field for decades -- how to go about their business.

Creation "science" as usual, eh?

Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.

The end result is an estimate or guess of what the age of the article is, and it should be given no more weight than that.

The end result is a method that can accurately date organic material for articles of known age. That is what RAZD's post above demonstrates. The correlation between Carbon-14 age and age determined by varve count, dendrochronology, and ice layer count all match. Calling this a "guess" is absurd. Only someone with an anti-science agenda would claim Carbon-14 dates are a "guess".

Anything concerning creation theory (or whatever you want to call it) does not enter into it, its just one of your red herrings presented in order to divert attention from the original issue. You rely on red herrings a lot dont you.

The truth is there are so many assumptions and variables these dating methods are based on the only scientifically honest answer is that they are an estimate/guess.

Here is a source from the NDT Resource Center so you cant reject it right off as 'creationist lies'

Radio-carbon dating is a method of obtaining age estimates on organic materials. The word "estimates" is used because there is a significant amount of uncertainty in these measurements. Each sample type has specific problems associated with its use for dating purposes, including contamination and special environmental effects. More information on the sources of error in carbon dating are presented at the bottom of this page.

As mentioned above, there is significant uncertainty in carbon dating. There are several variables that contribute to this uncertainty. First, as mentioned previously, the proportions of C-14 in the atmosphere in historic times is unknown. The C-14:C-12 atmospheric ratio is known to vary over time and it is not at all certain that the curve is “well behaved.”

Complicating things further, various plants have differing abilities to exclude significant proportions of the C-14 in their intake. This varies with environmental conditions as well. The varying rates at which C-14 is excluded in plants also means that the apparent age of a living animal may be affected by an animals diet. An animal that ingested plants with relatively low C-14 proportions would be dated older than their true age.

Attempts are often made to index C-14 proportions using samples of know age. While this may be useful to eliminate the uncertainty of atmospheric proportions of C-14, it does not compensate for local conditions such as which plant species are in the diet. The uncertainty in the measurement leads some to conclude that the method is far less predictive of age than is commonly supposed, especially for older samples

Edited by Admin, : Fix quotes. Ichiban, close quotes need a "/", as in [/qs].

Radio-carbon dating is a method of obtaining age estimates on organic materials. The word "estimates" is used because there is a significant amount of uncertainty in these measurements. Each sample type has specific problems associated with its use for dating purposes, including contamination and special environmental effects. More information on the sources of error in carbon dating are presented at the bottom of this page.

See the specific comments which follow.

As mentioned above, there is significant uncertainty in carbon dating. There are several variables that contribute to this uncertainty. First, as mentioned previously, the proportions of C-14 in the atmosphere in historic times is unknown. The C-14:C-12 atmospheric ratio is known to vary over time and it is not at all certain that the curve is “well behaved.”

That the levels of C14 in the atmosphere vary through time has been known for decades. De Vries published on that in 1958. That is why scientists have used a variety of methods to establish a calibration curve to account for that variation. That curve is based on tree rings, varves, corals and other annular data; and you know what? Those different methods are all in pretty close agreement!

Complicating things further, various plants have differing abilities to exclude significant proportions of the C-14 in their intake. This varies with environmental conditions as well. The varying rates at which C-14 is excluded in plants also means that the apparent age of a living animal may be affected by an animals diet. An animal that ingested plants with relatively low C-14 proportions would be dated older than their true age.

We know that! That is why radiocarbon dates are adjusted using the C13 level. Shellfish in my area often have a C13 of about 1.0 to -1.0, while plant material (and humans who feed on that plant material) are about -25.0. But recently I dated an individual who had a C13 of about -13.0 because he had a diet rich in marine organisms. So of course when I calibrated the date I used that information to correct the age; it reduced the age by some 400 years.

Attempts are often made to index C-14 proportions using samples of know age. While this may be useful to eliminate the uncertainty of atmospheric proportions of C-14, it does not compensate for local conditions such as which plant species are in the diet. The uncertainty in the measurement leads some to conclude that the method is far less predictive of age than is commonly supposed, especially for older samples

Again, C13 does correct for local plant species!

I haven't bothered to examine your source for these comments, but I'm not impressed.

(Scientists are not as dumb as some people would like to think.)

Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.

"The wretched world lies now under the tyranny of foolishness; things are believed by Christians of such absurdity as no one ever could aforetime induce the heathen to believe." - Agobard of Lyons, ca. 830 AD

I don't know if anyone has mentioned this, but creationists not only argue against the accuracy of 14C dating, they also argue for it. For example, the RATE group (a creationist dating group) argues that 14C dating is so accurate that they can date coal accurately to 50,000 years.

IchiBan writes:

Here is a source from the NDT Resource Center so you cant reject it right off as 'creationist lies'

Let me give you a little information that your source left out and you can decide for yourself whether they're lying.

NDT Resource Center writes:

The word "estimates" is used because there is a significant amount of uncertainty in these measurements.

If by "significant amount of uncertainty" they mean 5-10% for cases where there are no sample problems, then they are correct. But if they mean hundreds of percent of error as in something dated to 50,000 years old is actually 5,000 years old then they're incorrect.

Each sample type has specific problems associated with its use for dating purposes, including contamination and special environmental effects.

This is true. It is common for samples to present challenges, and the radiocarbon dating industry has developed a wide variety of approaches for dealing with this problem. For example, post-discovery contamination can be handled by placing a newly discovered sample in a sample container along with something known to have no carbon contamination. The sample and the carbon-sterile item are both dated, and any non-zero date for carbon-sterile item must be due to contamination and can be subtracted out. Rather than telling you about the techniques science has developed to address problems like contamination and then going on to question how this was done, they just chose not to tell you about it.

First, as mentioned previously, the proportions of C-14 in the atmosphere in historic times is unknown. The C-14:C-12 atmospheric ratio is known to vary over time and it is not at all certain that the curve is “well behaved.”

This was true at one time back when Libby first developed the process, but what your source doesn't tell you is that science has worked hard to rectify this, and we now have 14C profiles for the atmosphere going back the necessary 50,000 years. Rather than telling you that science has addressed this problem and then going on to question how this was done, they just chose not to tell you about it.

Complicating things further, various plants have differing abilities to exclude significant proportions of the C-14 in their intake. This varies with environmental conditions as well. The varying rates at which C-14 is excluded in plants also means that the apparent age of a living animal may be affected by an animals diet. An animal that ingested plants with relatively low C-14 proportions would be dated older than their true age.

It is true that this was once a problem, but your article doesn't mention that scientists have developed correction approaches that require measuring the 13C concentration. Rather than telling you about 13C-based corrections and then going on to question the effectiveness, they just chose not to tell you about it.

quote:The truth is there are so many assumptions and variables these dating methods are based on the only scientifically honest answer is that they are an estimate/guess.

It is true that a number of approximations and corrections are used when doing radiocarbon dating. However, exactly the same approximations and corrections were used to derive the calibration curves. These approximations and corrections cancel out when dating an old piece of wood. In effect, what we are doing when we date an old piece of wood is to measure its radiocarbon concentration and to match this to a tree ring which has the same concentration.

The only remaining assumption is that we can count tree rings.

(Note: I can think of only one minor correction which does not exactly cancel for wood dating: the time difference between when the unknown sample is dated and when the tree rings were dated. The radiocarbon decay during this time difference must be corrected for. In practice, this is done by converting all radiocarbon concentrations to what they would have been in 1950.)

I do have a question for Coyote and kbertsche since you guys have actually done work in the field:

Are or are there not some assumptions that come with this process? For example, nobody was around billions or millions of years ago to observe what the earth was going through at the time or what these samples went through as far as how they were affected by any sort of catastrophic event, and in discussing millions or billions of years, there's a good chance they went through quite a few catastrophic events, not just one.

One example, how do we know for certain what the initial amounts were to begin with? Isn't that an assumption? Has the rate of decay changed at all during time? How can anyone know that for certain?

One last question that I have that doesn't pertain to assumptions is, is C14 dating only good for geological samples or also for biological samples, or in an idiot laymen's terms, for dead animals, plants, leaves, ect??? Thanks in advance for the responses.